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The ocean has intrinsic variability arising from hydrodynamic instabilities of the time mean circulation, analogous to weather systems in the atmosphere. However, the ocean models typically used in climate assessments are too coarse and viscous to resolve these instability mechanisms, and this variability is strongly suppressed or entirely absent. Over the last two decades there has been tremendous progress in parameterizing the integrated effects of ocean eddies on the mean circulation, but the contributions to climate variability remain unrepresented. Recent pioneering integrations with high-resolution coupled climate models and the emergence of high-resolution global remote sensing observations allow us to begin to identify the geographical regions, space scales, and time scales at which the ocean may contribute to climate variability.

As we advance in the technological age our risk exposure to the space weather, severe storms in the near-Earth space environment driven by the complex magnetic field interactions at the Sun, continues to increase. The alterations in the ionized portion of the upper atmosphere driven by interaction of the complicated plasma and magnetic field structures emitted by the Sun, aka CMEs, and the Earth’s magnetic field can lead to significant degradations on the availability and accuracy of global positioning system (GPS). This interaction can also impact high-frequency (HF) radio communications forcing airlines to divert aircraft from trans-polar routings to longer lower latitude routes at significant costs. The severe storms can also drive strong currents in the electric power grid, potentially leading to blackouts, and long-distance pipelines, contributing to enhanced corrosion. Aspects of our understanding of the basic science behind these affects are quite good, but work remains to be done to create a robust, reliable, and effective set of forecast tools.

Modern modeling of space weather is accomplished through coupling of regional models of the thermosphere, ionosphere, and magnetosphere that can be driven by solar wind conditions taken from satellite observations or by the results of models of solar wind driven by solar coronal simulations. These numerical simulations can provide forecast of the space environment and are beginning to be transitioned into operations at NOAA’s Space Weather Prediction Center (SWPC) to provide information for government and industrial users. High Performance Computing (HPC) platforms allow simulations to be conducted at unprecedented resolution and over long simulation intervals. The large data sets produced by these simulations provide opportunities for novel discoveries through data mining. An excellent example of this discovery process is linkage of bursty bulk flows to magnetic reconnection in the mid-tail through high-resolution simulations. The future of space weather modeling includes many challenges. Key among these are the is the ability to predict the magnetic field inside the CME, utilization of new modeling techniques such as hybrid methods within the magnetospheric simulations, and development of a robust whole geospace model.

Measurements of atmospheric oxygen (O2) provide unique insights into global scale physical and biological ocean processes. During the HIAPER Pole-to-Pole Observations (HIPPO) campaign, which flew on the NSF/NCAR Gulfstream V research aircraft from 2009-2011, we measured the vertical, latitudinal, and seasonal distribution of atmospheric O2 with unprecedented precision and coverage. Subsequently, since 2012 we have been conducting continuous measurements of atmospheric O2 from the NSF ship ARSV Laurence M. Gould, operating in all seasons between Chile and the Antarctic Peninsula, and resolving the seasonal and latitudinal O2 variations over the Southern Ocean with even greater clarity. These recent in situ measurement programs leverage a multi-decade global network of flask sampling stations, with O2 measurements conducted by colleagues at Scripps Institution of Oceanography and other institutions. I will discuss the challenges in making these measurements and will present some of the insights we are gaining from them, including novel constraints on the thermal and physical forcing of Southern Ocean seasonal carbon exchange and an improved quantification of global north-south ocean heat transport. I will also confirm or reject the existence of a large Equatorial Pacific bulge in atmospheric O2 concentration, long suspected from a subset of global ocean biogeochemistry models but never well documented.

Living with a Red Dwarf: X-ray - UV Emissions and Flares of Red Dwarf Stars and Effects on Hosted Planets.

Red Dwarf (dM) stars are the most numerous stars in our Galaxy. These faint, cool, long-lived, and low mass stars make up ~ 75% of all stars in the Galaxy. Determining the number of red dwarfs with planets and assessing planetary habitability (a planet’s potential to develop and sustain life) are critically important because such studies would indicate how common life is in the universe. The "Living with a Red Dwarf" program was established to answer these important questions about the suitability of red dwarf stars to host planets where life could form and develop in complexity.

The program focuses on the magnetic-dynamo generated X-ray-Ultraviolet emissions and flare properties of red dwarf stars from youth (~10 Myr) to old age (~12 Gyr). As part of this program we have developed age-rotation-activity relations and also are constructing spectral X-UV irradiance tables for representative age-mass sample of stars. The ionizing X-ray-FUV radiation can have drastic effects on the hosted planet’s outer atmosphere while the stars’ UV radiation plays a major role in the photochemistry of the lower atmosphere and surface of the planets. Examples of selected red dwarf stars known to host potentially habitable planets will be discussed along an assessment of whether red dwarfs make suitable hosts for life-bearing planets.

Studies of Magnetic Reconnection from Flares to the Dayside Magnetopause

Active research areas at HAO are diverse, covering both the sun and Earth’s magnetosphere. To accommodate this diversity, this talk will be in the form of vignettes on a few recent theoretical and numerical results about magnetic reconnection in both settings. The talk will include the following: (1) We present a study of localized three-dimensional reconnection and how it spreads. The results are important for applications to two-ribbon solar flares, supra-arcade downflows, and reconnection in the solar wind. We find the behavior strongly depends on the out-of-plane (guide) magnetic field. (2) We present results on the nature of asymmetric magnetic reconnection in the presence of a flow shear, with applications to reconnection at Earth’s polar cusps when the interplanetary magnetic field points northward. We find surprising results for the effect of the flow shear on the reconnection rate and the motion of the reconnection site. (3) We study the properties and location of reconnection at the Earth’s dayside magnetopause. Studying dayside reconnection has been difficult because it is not trivial to find where it occurs. We present a technique to locate reconnection sites (separators) and results of studies of where reconnection happens and the efficiency at which it occurs, specifically addressing the local properties of the reconnection site in global magnetospheric simulations. (4) We present a new mechanism for fast reconnection that occurs even in the absence of the Hall term. It requires a guide field and relies on an anisotropic electron pressure, given by the double-adiabatic equations of state in this study. In addition to being of theoretical interest for understanding what makes reconnection fast, it may be relevant in the solar wind.

The upscale aggregation of convection is used to understand the emergence of rotating, coherent mid-tropospheric structures and the subsequent process of tropical cyclone formation. The CM1 model is integrated on an f-plane with uniform SST and prescribed uniform background flow. Moist cyclonic vortices form, merge, and eventually result in a single dominant vortex that subsequently forms a tropical cyclone. Consistent with previous studies, the approach to saturation within the mid-tropospheric vortex accelerates the genesis process. A novel result is that, while updrafts do not intensify prior to genesis, downdrafts do. Stronger downdrafts produce cold pools that maximize their negative buoyancy about one day prior to genesis. Shear-cold-pool dynamics promote organization of lower-tropospheric updrafts that spin up the surface vortex. It is inferred that the observed inconsistency between convective intensity and thermodynamic stabilization prior to genesis results from sampling limitations of the observations wherein the important cold pool gradients are unresolved.

The NCAR/UCAR Community Art Program cordially invites you to the opening art reception for two new exhibits. Gallery l features Gay E. Lasher, internationally recognized digital textile artist. Gallery ll features acyclic painter Michael “m.g.” Davis. The opening reception is Friday April 3, 2015 from 6-8 PM. Small appetizers and non-alcoholic drinks will be served. Live Jazz music by Ted Potter. The event will be held in the Mesa Lab cafeteria, 1850 Table Mesa Drive Boulder, CO. Come meet the artists and hear their stories as you enjoy their creations. Hope to see you there!

The Dominica Experiment (DOMEX) took place in the eastern Caribbean in the spring of 2011 with 21 research flights of the University of Wyoming King Air (UWKA) aircraft. The goal was an improved understanding of the physics of convective orographic precipitation in the tropics. The UWKA measured upstream and downstream airflow properties as well as the convective clouds and precipitation over the island of Dominica. This flight data along with an idealized numerical model have been used to understand the role of the ambient upstream wind speed in controlling the transition from thermally to mechanically forced moist orographic convection. Additionally, a modified version of Woodcock's 1960 moist convective initiation theory will be evaluated using a unique set of upstream sub-cloud measurements from DOMEX.

In order to support its forecast needs, the US National Oceanic and Atmospheric Administration (NOAA) has several operational Numerical Weather Prediction (NWP) systems, each requiring ongoing development to improve forecast skill. While the NOAA National Weather Service (NWS) centralizes the development and determines which updates are implemented in operations, research and development (R&D) are also conducted by the research branch of NOAA and by the academic community in general. This distributed model of development creates a potential for NOAA to benefit from a large body of scientific work, but also poses some challenges.

In order for scientists to contribute relevant R&D, it is important that they work with the current operational codes, suites, and relevant input datasets. However, obtaining such codes and inputs, and configuring the system to run with data assimilation and cycling workflows identical to the ones used in operations, can be a daunting task for those within and ouside of the NOAA Environmental Modeling Center (EMC).

To facilitate the use of operational NWP systems by the R&D community, NOAA has partnered with the Developmental Testbed Center (DTC) to create the design of the NWP Information Technology Environment (NITE). In this presentation we will review the various elements of the NITE infrastructure, which include data management, source code management and build systems, suite definition and configuration tools, scripts, workflow management system, experiment database, and documentation and training.

Advancing A Clean Energy Agenda in America: What Researchers Need to Know about Current and Future Renewable Energy Policy

Abstract:

Governor Bill Ritter led the successful effort to increase the State of Colorado’s renewable energy standard to 30% by 2020 in 2010. Establishing the most aggressive standard in the Rocky Mountain West, Colorado became both the first state to adopt a Renewable Energy Standard by a vote of the people and a national and international leader in developing a clean energy economy. Upon leaving office as Colorado Governor in 2011, Bill founded and took on the role as director of Colorado State University’s Center for the New Energy Economy. The Center works directly with policy makers, governors, planners, and other decision makers to create a road map that will accelerate the development of a new energy economy nationwide. It provides technical assistance to help officials create the policies and practices that will facilitate America’s transition to a clean-energy economy. In his talk, Bill will discuss the future of renewable energy, providing an overview on state, national and international policy trends and how these may affect renewable energy research and implementation.

James DoneThe National Center for Atmospheric ResearchBoulder, Colorado

An approach to assessing the damage potential of tropical cyclones is developed using a combination of physical reasoning and empirical assessment. Using readily available and key damaging cyclone parameters of intensity, size, and translational speed a Cyclone Damage Potential index is developed that represents offshore damage and onshore wind and coastal surge damage. The index is applicable to individual tropical cyclones, and to seasonal and global summaries. Actual damage assessment or prediction requires the additional step of incorporating historical damage data and regional peculiarities.

The index is then modified to use large-scale climate data available from global climate models, thereby sidestepping the need for information on individual cyclones. Relative sea surface temperature and steering flow are used as proxies for cyclone intensity, size, and translational speed. Application to climate model simulations under representative concentration pathways (RCPs) 4.5, 6.0, and 8.5 shows a future reduction in damage potential, driven by a cooling relative SST. However, the spread in damage potential reduction among the RCPs is less than the spread due to internal variability over the 21st century, as assessed using a climate model initial condition large ensemble. Improving understanding of spatial SST change may therefore be key to understanding future change in TC damage potential.

Richard Alley will deliver UCAR's next Walter Orr Roberts Distinguished Lecture on Wednesday, April 8 at 3:00pm in Macky Auditorium on the University of Colorado campus. Alley's talk, entitled “Ways Forward on Climate and Energy: Getting Good from What We Do and Don’t Know,” is part of the Conference on World Affairs. Alley is the Evan Pugh Professor of Geosciences in Penn State’s College of Earth and Mineral Sciences, and is best known to the public for hosting the PBS series, "Earth: The OPerator's Manual." Alley's research interests focus on glaciology, sea level change, and abrupt climate change. He is the recipient of numerous teaching and research awards and is widely credited with showing that Earth has experienced abrupt climate change in the past – and likely will again, based on his study of ice cores from Greenland and West Antarctica.

Alley's talk, as well as the entire conference, is free and open to the public. Be sure to arrive early to assure good seating.